Working through jBPM Process Designer Upgrade

I’m digging in to the embedded jBPM engine in Alfresco. I was using jBPM Process Designer 3.0.8 running in Eclipse 3.1.2, neither of which were the latest releases. Anticipating headaches, I decided to upgrade before moving on.

Eclipse 3.2.1 install is a breeze, including the addition of the Web Standard Tools and J2EE tools which used to be slightly painful. Now it is all automated through the update manager. Same with the Subclipse plug-in.
There was a problem with the jBPM 3.0.12 install, though. After expanding the zip and restarting, I was getting the following “java tooling” exception:

java.lang.NullPointerException
at org.jbpm.ui.util.JbpmClasspathContainer.getJarNames(Unknown Source)
at org.jbpm.ui.util.JbpmClasspathContainer.createJbpmLibraryEntries(Unknown Source)
at org.jbpm.ui.util.JbpmClasspathContainer.getClasspathEntries(Unknown Source)

This post had the answer. One of my old jBPM projects in the workspace was pointing to the old jBPM runtime. I think I could have edited the .classpath file to fix it but it was easier just to move my processdefinition.xml file, blow away the project, create a new one, and drop my processdefinition.xml file back in.